Question 18

What is the thickness measurement criterion for condemning a vessel?

The thickness measurement criterion for condemning a pressure vessel refers to the minimum allowable wall thickness below which the vessel is no longer considered safe for operation. If the measured thickness falls below this limit, the vessel may be declared unfit for continued use and may require repair, derating, or replacement.
In India, this criterion is determined based on design standards, corrosion allowance, and applicable safety requirements under the Factories Act, 1948 and relevant state factory rules, along with engineering codes issued by the Bureau of Indian Standards (BIS) or other applicable design standards.

The assessment typically considers:

  • Original design thickness of the vessel
  • Corrosion allowance provided during design
  • Actual measured thickness during inspection
  • Minimum required thickness for safe operation
  • Rate of corrosion and expected remaining life

If the measured thickness is below the calculated minimum safe limit, the vessel may be:

  • Condemned and removed from service
  • Repaired or strengthened
  • Re-rated for lower pressure operation (if permissible)

Uniquo uses precise thickness measurement techniques, including ultrasonic testing where required, to assess vessel integrity. Our inspection reports clearly indicate remaining life estimates, risk levels, and recommendations to help organizations ensure safe and compliant operation of pressure vessels.